Four-cycle internal-combustion engine



Sept. 16, 1930. CQX. 1,776,215

FOUR-CYCLE INTERNALHCOIBUSTION ENGINE File d Dec. 20. 4 Sheets-Shoat 1 a Z 0 x Sept. 16, 1930. F. J. cox 1,776,215

' FOURCYCLE INTERNAL COMBUSTION ENGINE Filed Dec. 20. 1927 '4 Sheets-Sheet 2 Sept. 16, 1930. F. J. cox 1.126.2

FOUR-CYCLE INTERNAL COHBUSTION EPIG I NE Filed Dec. 20. 1927 4 Sheets-Shut -3 gv wemtot 29 lfw aip Sept. 16, 1930. F. J. cox

FOUR-CYCLE INTERNAL COIIBUSTION ENGINE 4 Sheets-Shoot 4 Filed Dec. 20. 1927 gwuwntoz 47.60 2;

llll; LUL v Patented Sept. 16, 1930 are I FULTON J. COX, OF ALBUQUERQUE, NEW MEXICO FOUR-CYCLE INTERNAL-COMBUSTION ENGINE Application filed December 20, 1927.

This invention relates to four cycle internal combustion engines and more particularly to a multi-cylinder four cycle engine, wherein the cylinders are of the double acts yp a An important object of the invention is the provision in an engine of this character of a construction and arrangement such that the crank shaft of the engine is given an impulse from each cylinder twice during each four cycles of operation, thereby obtaining a two cycle effect with a four cycle operation.

A further object of the invention is to provide a construction such that the power impulses are so appliedthat a smooth even flow of power is obtained.

A further object of the invention is to provide valve mechanism for the control of the engine, permitting use of such a construction in this manner.

A further object of the invention is to pro duce a structure, such that the parts of the engine are rendered readily accessible and repair is accordingly facilitated.

These and other objects I attain by the construction shown in the accompanying drawings, wherein for the purpose of illustration is shown a preferred embodiment of my invention and wherein Figure 1 is a vertical sectional view through an internal combustion engine con: structed in accordance with my invention;

Figure 2 is a section on the line 2-2 of Figure 1;

Figure 3 is a section on the line 3-3 of Figure 1;

Figure 4 is a combined detail view showing the positions of the various valve elements and cams with the parts of the engine in position illustrated in Figure 1;

Figure 5 is a diagram showing the cycle of operation of the engine, the vertical line indicating the position in which the engine is illustrated in Figure 1.

Referring now more particularly to the drawings, the numeral 10 generally designates a cylinder block, at present illustrated as having four cylinders. formed therein.

Secured to the ends of the block in any suit- Serial No. 241,381.

able manner are upper and lower heads 12 and 13, each having intake and exhaust ports 14 and 15 controlled by spring seated poppet valves 16 and 17. The lower head 13 is provided with a flange which is secured, as at '55 18, to the engine base 19. The poppet valves of the upper head have their stems contacted by rocker arms 20 supported from the head and these rocker arms are actuated by push rods 21, the lower ends of which operate in 0 guides 22 carried by the flange 18. Beneath the lower ends of these guides are disposed cam shafts 23, which are so connected with the crank shaft 24 of the engine that they rotate oppositely to one another and at one-half of the speed of the crank shaft. The direc tion of rotation of the cam shafts is indicated by the arrows in Figures 2 and 3.

Within the cylinders operate pistons 9 having rods 25 rigidly secured thereto, and extending through guides 26 carried by the lower cylinder head. These pistons subdivide the cylinders into chambers which have been designated by numerals l, 2, 3, 1, 5, 6, 7 and 8. The poppet valves of the lower head which control the chambers 5, 6, 7 and 8 are operated by rocker arms which are divided into two groups, the rocker arms of one group being indicated by the reference character 29 and controlling the operation of the valves I, I

of the chambers 7 and 8. These rocker arms oppose the cam shafts with which they co-operate at the inner faces of said cam shafts and accordingly because of the direction of rotation of the cam shafts, are engaged by the cams 28 thereof subsequently to the engagement of the cam shaft with the tappets 21, the points of engagement being circumferentially spaced through approximately of rotation of the cam shaft. The rocker arms ofthe second group are indicated at 27 and oppose the cam shaft at the outer face thereof, so that their operation by the cams 28 takes place prior to the operation of the tappets 21. Each cam 28 operates a rocker 9 arm 27 or 29 and likewise operates a tap pet 21.

By reason of this arrangement, each pair of intake and exhaust valves for the cylin ders may be operated by a single cam. In the engine greatly facilitated.

willbe rigidly fixed to the rods 25 and the present instance, I have shown two sets of intake and exhaust valves for each cylinder, although it will, of course, be understood that if desired, a single set may be employed. Further, by reason of this arrangement, the cycle of operation of the chambers 1 and 2 is advanced through 90 of rotation of the cam shaft or 180 rotation of the crank shaft over their associated chambers S and 7, while the cycle of operation of the chambers 3 and 4 is retarded through a similar distance with relation to the cycle of their associated chambers G and 5. By employing this arrangement, using the double acting cylinders, two impulses are given the crank shaft from any given crank for each four cycles of oper ation, and at the same time a firing order is provided which permits an operation similar to that of an ordinary eight cylinder engine.

in the illustration provided in Figure 1, the

operations are indicated by legends and it will be obvious upon consideration that with the arrangement illustrated and described,

an explosion will take place at each 90 of rotation of the crank shaft.

Because of the arrangement employed, the heads may be readily removed for operations upon the valves and the repair of the The pistons 9 guide construction preferably includes a cross head slide 30 for coaction with the cross heads 31 carried by the rods, so that no side strain will be placed against these pistons.

upper and lower ends, a piston slidably' mounted. in each cylinder, a crank shaft having arms set at 90 with relation to each other, means operatively connecting the arms and pistons, a pair of upper and lower admission valves for each cylinder, a pair of upper and lower exhaust valves for each cylinv der, a pair of cam shafts geared with the crank shaft to rotate at one half of the rate thereof, a cam on one cam shaft for each pair of upper and lower admission valves, a cam on the other cam shaft for each pair of upper and lower exhaust valves, a follower connected to the upper valve of each pair, a rocker arm connected to the lower valve of each pair, and the follower and rocker arm of each pair of valves contacting with each cam at points spaced 90 apart.

2. An internal combustion engine comprising four cylinders having chambers at their upper and lower ends, a piston slidably mounted in each cylinder, a crank shaft having arms set at 90 with relation to each other, means operatively connecting the arms with tl e pistons, a pair of upper and lower admission valves for each cylinder, a pair of upper and lower exhaust valves for each cylinder, a pair of cam shafts geared with the crank shaft to rotate at one half the rate thereof, a cam on one cam shaft for each pair of the admission valves, a cam on the other cam shaft for each pair of the exhaust valves, a follower connected to the upper valve of each pair, rocker arm connected to the lower valve of each pair, the follower and rocker arm of each pair of valves contacting with each cam at points spaced 90 apart, all of the followers contacting with the upper sides ofthe cams, the rocker arms of two of the cylinders being pivoted above the cam shafts and contacting with the inner sides of the cam, and the rocker arms of the other cylinders being pivotedbelow the cam shafts and contacting with the outer sides of the cams.

In testimony whereof I hereunto affix my signature.

FULTON J. COX. 

